Can you play the asphaltophone

Can you play the Asphaltophone?

When you drive over lumps and bumps on the road, the sounds rumble up into your car. But you might be surprised to learn just how much road makers can control theses sounds.

The phenomena of encoding music and tones into road surfaces was originally discovered in the 1950s – using parallel corrugations in the tarmac. But it was not until 1995 that Danish artists Steen Krarup Jensen and Jakob Freud-Magnus invented the ‘Asphaltophone’. Today, ‘musical roads’, ‘singing roads’ and ‘melody roads’ can be found all over the world.

Test your mental music muscles!
If the distance between the corrugations on a musical road is 16 cm:

  1. What tone do you get if you drive a constant speed of 100 km/h (62 mph)?
  2. How fast would you have to drive to hear the tone ‘C4’?

(Assume the concert pitch was tuned at 440Hz.)

Asphaltophone! Quiz answer
When you drive 100 km/h, which is equal to 27.8 m/s, you will pass 173.6 corrugations per second, which will radiate a fundamental frequency of 173.6 Hz, corresponding to an F tone in the third octave. Therefore:

  1. When you drive down the described road at 100 km/h (62 mph), you will hear the tone ‘F3’.
  2. To hear the tone ‘C4’ you would have to drive 151 km/h (94 mph).